With the continuous increase of the exploration degree of oil reservoirs, an oil-gas exploration area gradually changes from a middle shallow layer to a deep layer and an ultra-deep layer, and deep oil-gas resources are important fields of the future oil-gas resource development. Water injection and gas injection are important measures for the development of deep oil reservoirs, but long-term water injection or gas injection aggravates the heterogeneity of the reservoir, and cross flow is easy to occur, so that the water content of an oil well rises quickly, and the development level is reduced to some extent. The profile control and water shutoff of the ultra-deep reservoir is an important technology for improving the development effect of water injection or gas injection, and the gel type plugging agent has wide application space in the field of profile control and water shutoff by controlling the gelling time and adjusting the gelling strength. However, ultra-deep reservoir is exposed to complex severe reservoir conditions of ultra-high temperature (not less than 130° C.), ultra-high salt (not less than 20 ten thousand mg/L) and ultra-high pressure (not less than 50 MPa), and the exiting gel system has poor stability and is easy to degrade, so that the gel type plugging agent has poor profile control and water plugging effects.
CN108300440A disclosed a nano-graphite emulsion reinforced body jelly system for jelly dispersoid, a composition, a preparation method and an use thereof, which contained a polymer matrix, a resin cross-linking agent, a coagulant and nano-graphite emulsion, could form a high-strength body jelly system within 3-6 h at 85-95° C., and the obtained jelly dispersions has high temperature resistance and salt resistance. Because the system had short gelling time, the deep injection was difficult for the ultra-deep reservoir, and the process measures for profile control and water shutoff were limited.
CN103232839A disclosed a water plugging agent suitable for water plugging and profile control of a high-temperature and high-salinity oil reservoir, wherein the water plugging agent consisted of a main agent, a cross-linking agent, a stabilizing agent and the balance of water, the gelling time was 5-28 h the temperature resistance was 150° C., and the mineralization resistance was 2.0 multiplied by 104 mg/L, but the liquid preparation of the system only uses clear water, the liquid preparation of high-mineralization water cannot be met, and the field use was limited.
Therefore, the research and development of the composite temperature resistance gel plugging agent which is resistant to high temperature and high salt and can be suitable for profile control and water plugging of the ultra-deep reservoir have important significance.